Crank-case ventilation



May 27, 1930. R. cLAsoN 1.7605336 CRANK CASE VENTILATION 'med oct. 2s, 1927 Patented May 27, 1930 NETE!) STATES rar RAGNAR CLASON, OF FLIN'I, MICHIGAN, ASSIGNOR T0 A C SPARK PLUG COMPANY, OF FIJINT, MICHIGAN, A lCOMPANY F MICHIGAN CRANK-GASE VENTILATION Application led October 29, 1927. Serial No. 229,687.

This invention relates to crankcase ventilation for an internal combustion engine and is particularly adapted to use in an internal combustion engine of an automotive vehicle.

It is an object of the invention to provide a new and improved means for regulating` the Ventilating current of air passed through the engine crankcase during operation of the engine. More specifically it is an object of the invention to provide a Ventilating system operated by the suction of the air intake with means for maintaining the current of air through the crankcase substantially constant at any speed of the engine or for reducing the current during high speed when the crankcase oil is heated and the diluents are readily volatilized.

Other objects and advantages of the invention will appear in the course of the following description, taken in connection withA the accompanying drawing and appended claims.

In the drawing:

Fig. 1 is a plan view partly broken away 7 of a conventional internal combustion engine trated a conventional internal combustion enn gine comprising an engine block 10, crankcase 12, intake manifold 14, and carbureter 16. 17 indicates the engine valve compartment located at one side of the cylinders which are indicated by the dotted circles in Figure 1. The valve chamber is closed by means of the usual removable cover 19. On the cover 19 is mounted a cover 18, which together with the cover 19 forms an air chamber. A pipe 20 fitted in an aperture in the cover 19 establishes communication between the air chamber and the valve compartment. A baffle 21 is secured to the cover 19, and eX- tends over the pipe 20 to shield it against the entrance of oil. A conventional air cleaner 22 is xed in an opening in the cover 18, and fixed, to the inner side of the cover 18 as by rivets 24 is a flap valve 26.A The valve is of spring material and normally covers the inner opening of the air cleaner butl is adapted to swinginward to nearly close the pipe 20,

the outer end of the pipe 20 being sheared atan angle to coincide with the inner position of the valve 26, as shown in Fig. 1.

At the opposite end of the air chamber is connected a pipe leading to the carbureter. At the front end of the engine I have provided a conventional breather pipe 32 opening into the crankcase.

When the engine is running at low speed, there is but a slight vacuum within the air chamber and all the air drawn to the manifold. through the pipe 30 comes from the crankcase. As the speed of the engine increases, the vacuum in the air chamber increases and the flap valve 26 starts to open, admitting air through the cleaner 22. As the speed of the engine continues to increase the valve 26 opens wider and almost but not quite completely shuts of the current through the pipe 20. As the speed of the engine decreases, the action of the valve is just the reverse of that described. The valve thus acts as a damper for the Ventilating device and insures that the current through the crankcase will not become great enough to draw out fine particles of oil into the air chamber, as would be the case if the current through the crankcase increased directly with the speed of the envine.

b In the modification shown in Figs. 3 and 4 the air chamber is provided by a casing 40V rigidly fixed on the forward side of the car-v the endof the pipe 46 which leads to thecrankcase above the level of the oil. The operation of this form of my invention is similar to that described above., While it is convenient to provide an air chamber as illustrated, I desire it to be clearly understood that the air chamber itself is not absolutely necessary and tha-t it is necessary only that there be a connection between the air intake and crankcase sufficiently large to mount therein t-he compensating valve described.

I claim: A

1. An engine having a crankcase, means for admitting air to the crankcase, said crankcase being provided with an air outlet ort. a suction connection commu'nicatinor` f C with said outlet port, a port opened to the atmosphere communicating with said suction connection, and means cooperating with both of said ports and normally closing one or said ports, said means being movable to vary the opening or closing of the ports.

2; An engine having a crankcase, means for ,admitting air to the crankcase, said 'cranlca'se being provided with an air outlet port, a suction` connectionA communicating with said outlet port, Va port open to the atmosphere communicating with said suction connection, and suction operated means cooperating `with said ports and normally closing the last port and being adapted upon application of suction to gradually open said last named port and close said iirstV named port.

3. An engine having a crankcase,vineans forV admitting air to the crankcase, said cranlrca-se being provided with an air outlet port, a suction connection communicating with said outlet port, a port open to the atmosphere communicating with said suction connection, and a valve overlying both of said ports and movable to open one port and close the other. x

4. An engine having a crankcase, means for admitting air to the crankcase, said crankcase being provided with an air outlet port, a suction connection communicating with said outlet port, a port opento the atmosphere communicating with said suction connection, and a suction operated valve eX- tendingbetween and overlying said ports, saidvvalve being spring tensioned to normally close said atmospheric port.

5. An engine having a crankcase, means for 'admitting air to the crankcase, 4said crankcase being providedv with an air outlet port, a suction connection communicating 'with said outlet port, ja port opento the atmosphere communicating with said suction connection, an'd a springl plate 4extending between `1ndoverlying said ports, said plate normally closing said atmospheric port and being adapted tocbe flexed by the application of suction to gfradually` open said atmospheric port and close said crankcase port.

6. An 'engine having a cranlcase having au airlinlet, an air chamber provided with a suction port, a port connecting the crankcase and chamber, an, atmospheric port leading into the a'i'r chamber, and a suction Voperated valve in said chamber lnormally closing said last named port and adapted upon application of suction to gradually open said atmospheric port and close said crankcase port.

7. An engine having a crankcase having an air inlet, an air chamber provided at one end with a suction connection, and at the other end with a port connecting the crankcase and chamber, an atmospheric port leading into the air chamber, and a suction operated valve in said chamber extending between and overlying said last named ports and `adapted upon application of suction to gradually open said atmospheric port and close said crankcase port.

8. An internal combustion engine provided with a crankcase having an air inlet,

a valve chamber in communication with the cranlicase, an air chamber provided with a suction connection, a port connecting said chambers, saidvair chamber being provided with an atmospheric port, and means in said air chamber normally closing said atmospheric port and adapted upon application of suction to open said atmospheric port and close'V said crankcase port.

- 9. In combination with a pair of opposed ports, a flap valve extending between and overlying said ports and adapted to normally close one of said ports and to be swung into position to close the other of said ports, said other port having its seating end. cut on a lradius drawn from the axis of oscillation of the valve;

In testimony whereof I aiiix signature.

RAGNAR CLASON. 

